Supersymmetry squeezed at the high-energy frontier

First year Oxford graduate student Jesse Liu has just released a paper showing how the increase in LHC energy from 8 to 13 TeV has squeezed the permissible models of the theory of supersymmetry.

Supersymmetric theories predicts particles that could help explain the mysterious dark matter in our universe, and which can be produced at the LHC, so they are well worth pursuing.

The paper, which makes use of several searches performed by the ATLAS collaboration with data recorded during 2015, extends constraints on SUSY models. It shows increased sensitivity relative to the previous state-of-the-art - a study of 8 TeV data undertaken within the ATLAS collaboration, which also had major Oxford involvement.

With the help of Oxford Advanced Research Computing, Jesse considered more than a hundred thousand supersymmetry models. The supercomputer simulated more than 3 billion computer-generated collisions, each producing candidate supersymmetric particles.

A computer simulation of a supersymmetry event in a LHC detector

Our results show that there is already an increase in sensitivity, particularly to the gluino - a partner partner of the gluon which holds the nucleus together. Insights from the analysis will provide valuable information to aid the ATLAS collaboration in future searches.

As Jesse explains, “We reveal where ATLAS have not yet searched so they can design new and improved strategies to see where supersymmetry could be hiding”.

More information about the Oxford Supersymmetry group can be found on the group web pages. The group is led by Professor Alan Barr.